I am not president for a certain term...but until we conduct parliamentary elections. And presidential elections. And we finish drafting the constitution.

The military had said that Mansour will only retain power until full presidential elections can take place, although no time scale has yet been released.

Members of the Muslim Brotherhood shout outside the Constitutional Court during the swearing in ceremony Adli Mansour. Credit: Reuters

Ousted President Morsi and a great number of his supporters and those in his Muslim Brotherhood party have been arrested and pro-Morsi TV channels have been taken off air.

The international community has been cautious over the change in governance with David Cameron saying what was most important for Egypt now was for democracy to flourish and for a "genuine democratic transition to take place."

France denounced the moves, with President Francois Hollande says the democratic process in Egypt has stopped and must return.

Tunisia's ruling Islamist party, Ennahda, also condemned what it called a "coup against legitimacy" after the army ousted Egypt's first democratically elected president.

"Ennahda rejects what happened and believes legitimacy is represented by President Mohamed Morsi, and no one else," said a statement from the party, which has headed the Tunisian government since 2011.